Method of winding artificial thread



@et 9, 1934. F. GIRARDET METHOD OF WINDING ARTIFICIAL THREAD Filed Dec. 1l. 1930 ATTORNEY Patented Oct. 9, 1934 UNITED STATES 'PATENT OFFICE Franois Girar-det, Grenoble, France, assignor to Du Pont Rayon Company, New York, N. Y., a corporation of Delaware Application December 11, 1930, Serial No. 501,495 In France December 12, 1929 6 Claims.

This invention relates to the manufacture of artificial silk, and more particularly to a method of collecting or winding artificial thread in a centrifuge or bucket and the cake resulting therefrom. v

There are two processes at the present time employed in the production of articial thread. One of thesemethods is known as the bucket process and it is to this process that the invention 10 relates. According to the bucket process of producing artificial thread, the thread, after being coagulated and/or regenerated, is drawn from the bath or baths effecting the coagulation and/or regeneration by a, godet wheel, from which it is led into a rotating centrifuge where it iswound, due to the centrifugal force, to form a package of thread known as a cake.

The bucket employed in this process is provided with a cover usually disposed on a seat or shoulder and held in place by some mechanism, such as a spring, which cooperates with a groove in the bucket. The cover is formed with a central aperture through which a thread guide passes and conducts the thread into the bucket. In

order to build the cake, a uniform vertical reciprocal movement is imparted to the thread guide, the stroke being constant throughout the formation of the cake.

A cake produced according to this procedure is in the form of a truncated cone having a hollow core similarly shaped. The'top of the cake, i. e., that surface which is formed beneath vthe cover, and the bottom, i. e.,` that surface which is formed on the .bottom of the bucket, are provided with relatively large bases.

The cover employed in the processes used prior to this invention was indispensable, since it served to prevent the upper layers or windings of the thread from projecting out of the bucket.

40 Nevertheless, it had several serious disadvantages. Both the cover per se and the means, such as the spring, which held it n place oiered resistance to the movement lof air during rotation and thus increased the power consumption.

' 45 Moreover, the cover had to be removed in order to remove the cake. This operation required careful manipulation, and precautions Awere necessary not to engagel the thread which was still 6 in a very fragile and weak condition.

ducing artificial thread I can wind articial thread, after it has been coagulated and/or regenerated, in a bucket, preferably coverles, by progressively reducing the stroke of the thread guide conducting the thread into the bucket acteristics of the rotating bucket.

I have found that in the bucket process of proeither at the beginning of the winding operation or after the bases have been formed, and produce a cake containing a substantial quantity of thread which is not affected by the windage char- It is therefore an object of this invention to provide a method of producing artificial thread wherein the artificial thread is conducted in a bucket, preferably coverless, to produce a cake containing a substantial quantity of thread which is not affected by the windage characteristics. of the rotating bucket by progressively reducing the stroke of the thread guide conducting the thread into the bucket, said reduction in stroke being effected at the beginning of the operation or after the bases have been produced.

Another .object of this invention is to provide a new package of thread, i. e., a cake resulting from a process wherein the stroke of the thread guide is progressively reduced at some stage of the winding operation and preferably after the bases have been produced.

Other objects will appear from the following description, appended claims and accompanying drawing in which:

Figures 1, 2, 3 and 4 illustrate longitudinal sections of several forms of cakes produced in accordance with the principles of this invention.

According to this invention, artificial thread, after formationin any well known manner and g5 in combination therewith, is conducted into a. rotating coverless spinning bucket by av thread guide having a reciprocating movement, wherein the stroke is progressively decreased between the top and bottom of the bucket. The decrease in'the stroke of the thread guide may be begun immediately after one layer of windings has been formed. Preferably, however, the stroke of the thread guide is not decreased until a plurality of layers of thread have been wound. This results in the formation of a cake which has small bases at the top and bottom thereof,

In Figure 1 there is illustrated one form of a cake which may be secured by carrying out one modication of the method constituting one part of this invention. The cake 1 is produced by conducting a rayon thread, after formation, into a rotating spinning bucket. At the beginning of the winding operation, the thread guideY is uniformly reciprocated and this procedure is carried out until the desired width of the bases 2 and 3 is produced. Subsequently, the stroke of thethread guide is uniformly and progressively reduced between the top and bottom of the bucket during the remainder of the operaon. 1m

Though the ba'ses 2 and`3 may be made of any width, they are usually of such dimensions that, in the absence of a cover on the bucket, outward projection of the thread may be impossible, and at the same time a minimum surface may be exposed to friction during handling.

It is apparent that the movement of the thread guide may be made inaccordance with any formula or curve. For instance, when the decrease of the stroke follows 'a rectilinear function, a cross-section of a cake similar to that shown in Figure 1 may be obtained. If, however, the progressive decrease in the 'stroke of the guide follows a curvilinear function, the cross-section of the cake may be, for example, that illustrated in Figure 2.

As previously mentioned, though it is preferable to begin the reduction of the stroke of the thread guide in the bucket after the bases 2 and 3.have been formed, this is not essential for the successful practice of the invention. -The bases 2 and 3 may be wholly omitted and, when this is desired, the alternating decreasing movement of the thread guide is begun at the beginning of the operation. Figures 3 and 4 illustrate two forms of cakes produced according to this modification.

From the above it is apparent that I have devised a method wherein a coverless bucket may,

be employed, thus overcoming the disadvantages present when covered buckets are employed. The method herein described results in a new form of cake. Though the external appearance is of a truncated cone, the cakes have hollow cores, the shapes of which are functions of the manner of Vwinding as herein described.

Since itis obvious that various modifications may be made in the specific details described above without departing from the spirit or nature of the invention, the invention is not restricted thereto except'as defined in the appended claims.

I claim:

1. A method of producing artificial thread which comprises spinning a cellulosic solution to form an artificial thread and conducting the freshly produced thread into a rotating bucket by progressively decreasing the stroke of the thread guide between the top and bottom of the bucket;

2. A method of producing artificial thread which comprises spinning a cellulosic solution to form an artificial thread and conducting the freshly prepared thread into a rotating bucket by uniformly reciprocating the thread guide until the desired width of base is secured and -then conducting additional freshly prepared thread into said bucket by progressively decreasing the stroke of said thread guide between the top and bottom of the bucket.

3. A method of producing artificial thread which comprises spinning a cellulosic solution to form an artificial thread, and conducting the freshly produced thread into a rotating bucket by progressively decreasing the stroke of the thread guide between the top and bottom of the bucket in accordance with a curvilinear function.

4. rA method of producing artificial thread which comprises spinning a cellulosic solution to form an artificial thread, and conducting the freshly produced thread into a rotating coverless bucket by progressively decreasing the stroke of the thread guide between the top and bottom of the bucket to produce a 'cake containing a substantial quantity of thread which is not affected by the windage characteristics of the rotating bucket.

. 5. A method of producing artiiicial thread which comprises spinning a cellulosic solution to form an artificial thread, and conducting the freshly produced thread into a rotating coverless bucket by progressively decreasing the stroke of the thread guide between the top and bottom of the bucket in accordance with a curvilinear function to produce a cake containing a substantial quantity of thread which is not affected by the windage characteristics of the rotating bucket.

6. A method of producing artificial thread which comprises spinning a cellulosic solution toY form an artificial thread, conducting the freshly prepared thread into a rotating coverless bucket by uniformly reciprocating the thread guide until .the desired width of base is secured and then conducting additional freshly prepared thread into said bucket by progressively decreasing the stroke of said thread guide between the top and bottom of the bucket in accordance. with la curvilinear function to produce a cake containing a substantial quantity of thread which is not affected by the windage characteristics of the rotating bucket.

FRANCOIS GIRARDET. 

